In vehicles, particularly in passenger cars, safety-belts are normally used to secure those travelling in the vehicle. In a known manner, the safety-belts add to the safety of those travelling in the vehicle. A common kind of safety-belt is the so-called three-point belt which comprises a belt attached to a retracting device which is normally arranged on the body of the vehicle, at the side of the seats. The belt runs from the retracting device, across the torso of the passenger or driver. Normally, at the level of the one shoulder of the passenger or the driver, there is an upper belt guide through which the belt runs. The belt is fastened by a locking means at an attachment point on the side of the driver or the passenger. The belt also runs through a guide at this attachment point, and runs across the waist of the driver or passenger. Finally, the belt is fixedly attached to the floor of the vehicle on the opposite side of the driver or passenger relative to the attachment point.
In terms of the function of the safety-belt, it is an important requirement that the above mentioned upper belt guide is arranged so that the belt runs through it at a point close to the shoulder part of the driver or passenger when sitting in an upright position, i.e. with the backrest in an upright position. In this way optimal protection can be obtained from the safety-belt in a possible collision. The belt in this manner runs through the belt guide close to the shoulder of the driver or passenger, across the chest of the driver or passenger, through another belt guide at the lower attachment and guide point, and across the waist of the driver or passenger towards the fixation point.
Although conventional seat belts of the three-point type provide good protection in most normal situations they are somewhat inadequate in those cases where the driver or passenger sits in a position somewhat different from the normal, i.e. upright position, which has been described above. In particular, conventional three-point belts do not provide optimal safety if a passenger wishes to recline the backrest in order to rest or sleep when travelling in the vehicle. This is particularly relevant for a passenger who sits in the passenger seat next to the driver. If the backrest of the seat is reclined, the upper guide point of the safety-belt will be at a point a long way in front of and above the shoulder of the passenger. Thus, the safety-belt cannot provide optimal protection in case of a collision.